1. Field of the Invention
The invention relates to a fan frame structure, in particular, to a fan frame structure having a plurality of clearances to increase the side-airflow of the fan.
2. Description of the Related Art
With the growth in the development of electrical products, the radiation performance of the fan has become an important subject matter. FIG. 5 is a pictorial view showing a conventional fan structure. Referring to FIG. 5, the fan includes a fan frame 100 and an impeller 200. The impeller 200 is located in the fan frame 100. An inlet 101 and an outlet 102 are formed on the fan frame 100 for the air to flow in and out, respectively.
In the above-mentioned fan, it is preferred that the inlet 101 is as large as possible. Thus, if the area of the inlet 101 is increased or extra inlets are added, the airflow from the fan can be increased to improve the radiation performance of the fan.
It is therefore an object of the invention to provide a fan frame structure having a plurality of clearances so as to increase the side airflow into the fan.
According to one aspect of the invention, a fan frame for encircling an impeller of a fan includes a base and a plurality of teeth. A hole is formed in the base to form an inner periphery. The plurality of teeth is substantially perpendicular to and mounted around the inner periphery for encircling the impeller of the fan. A plurality of clearances is formed between each one of the pluralities of teeth and its adjacent tooth.
According to the above-mentioned structure, the plurality of clearances can increase the inlet area of side airflow to improve the performance of the fan.
The fan frame may further include a motor mounting plate located at the center of the hole, and a plurality of ribs connecting the inner periphery of the base to the motor mounting plate for holding the motor mounting plate.
In addition, each of the plurality of teeth is arranged along, and is parallel to, or not parallel to, a tangent of the inner periphery.